Google, one of the world’s largest users of data, may finally be making good on a five year-old patent to build offshore data centers — cooled and powered by the ocean, and potentially beyond reach of the government.

An investigative report by CNET Friday (here) found a great deal of evidence connecting the search giant to the mysterious “Building 3″ on Treasure Island in San Francisco Bay, above. The building seems to the base for a mysterious four-story structure on a nearby barge that experts say is consistent with a floating data center.

Meanwhile, a very similar four-story building was towed on a barge into harbor in Portland, Maine, two weeks ago. On Wednesday, the Portland Herald speculated (here) that the barge may have something to do with Google’s offshore data center patent.

The Portland barge is registered to the same shell company connected to the Treasure Island operation, called By And Large — very similar to the fictional “Buy and Large” company featured in several Pixar movies. It seems someone at Google is a Pixar fan.